"Absolute best" used speaker for $8-10K

Knowing some of the above mentionned products I would STRONGLY recommend listening to the Ayon Falcon S speakers if you like extreme transparency, soundstaging, detail retrieval, speed and neutrality. The Ayons are pretty dynamic but no real bass-wonders like B&W 800 or the Sophias but exceed these particular products in ALL other areas. Far better and more dynamic and engaging than Avalon Opus Ceramique.
A speaker to last a life time. Hope this helps.

You mentioned a preference for female vocals/jazz. Diana Krall "The Look Of Love" won a Grammy for Best Engineered Album in 2002. I believe it was mastered by Doug Sax on ATC SCM 100ASL's. These speakers are currently listed on audiogon used for $7500 obo.

Not necessarily the "Absolute Best". Seriously, can any speaker claim that title when so much depends on room acoustics and aesthetic needs?

Given you plan to spend that much money, these speakers have a heritage in pro use that should give you more confidence than the all too common glowing audio magazine review or web testimonials from people you don't know.

I would also recommend the Ayon Falcon S. The only drawback is that it is available only new with a current wait time of three months and I seriously doubt that anyone who has it would sell it.

I´ve just exchanged Avalon Opus Ceramique with Falcon S - a HUGE upgrade.. Kens, you are right: under normal circumstances you´ll have to wait until march 07` - but it´s def. wortn waiting for it although retail is € 13.000,- which is approx. US $ 16.500,00..

Thiel 7.2 , at the Munich Audio show, the audience liked them more than the WA Alexandria and JM Lab Grande Utopia BE.
All speakers were in the same room/equipment.